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sciencehabit writes "Lying in bed, unable to move a muscle, so-called locked-in patients have few ways to communicate with the outside world. But researchers have now found a way to use the widening and narrowing of the pupils to send a message, potentially helping these patients break the silence. The trick is a webcam-like setup that tracks pupil dilation. When people focus on a hard problem--say a math problem--their pupils dilate. Employing the approach, some locked-in patients could answer 'yes' and 'no' questions just by dilating their eyes."

That's about the first thing the locked-in patient Jean-Dominique Bauby [wikipedia.org], who wrote a book by blinking his eyes, said. The book is an amazing read, breathtakingly beautiful and intelligent. Bauby died a bit after the book was released..

While I am genuinely interested in seeing real, functional communication with a demographic that is typically cut off from being able to communicate with the rest of the world, I am very skeptical that this is going to turn into yet another facilitated communication hoax.

On the plus side (and notably unlike 'facilitated communication', which required a true-believer to be in immediate contact with the patient), it would be reasonably trivial to pipe eyeball-cam footage to an otherwise blinded observer.

Doesn't mean that hopefully families won't be conned (or con themselves) into playing sick human-Ouija-board games with locked-in patients; but "Is this pupil dilation pattern conveying information?" should be a pretty testable question.

Oh, 'facilitated communication' was quite the clusterfuck. Mostly preyed on severely autistic or otherwise nonverbal children (and if you think that dead people have an affective grip on our little hominid brains, try crippled kids...) Eventually started to come unglued when some of the communications facilitators began making (by means of their helpless meat-puppets) allegations of child sexual abuse against parents... Thankfully, 'facilitated communication' mostly crumbled under the onslaught of actual te

Thank you for your feedback. I was actually hoping to hear someone with specific experience with these techniques share their impression of the technique.

Can you expand on your experience with this technique? How did it work in your late wife's case? What was the latency of the communication like due to the obvious bandwidth constraints of this particular medium?

It was slow. There was no blink required. The scanner registered how long the eye focused on a particular point to activate the "click". The dwell time was tunable, so you could adjust it as you became more practiced at it.

Because *everything* for an ALS patient is exhausting, it was very tiring for her to use. But it was worth it, even if it took a long time for her to spell out what she wanted. Predictive text also helped.

The biggest PITA was getting the positioning "just right" when we moved it f

So in all seriousness, if you're paralyzed down to your eyeballs, how can your pupils dilate/contract? That's not a nerve thing? According to TFA, the dilation shows your brain stem is intact, but that some people couldn't even move or blink their eyes for yes/no responses. If they can't move their eyes, how can the nerves dilate them? I can see the blinking being separate nerves, but would think moving and dilation and focusing would be pretty closely related? Bad assumption?

Unable to blink, I can understand. The muscles that point your eyes and close and open the iris are cranial nerves that begin inside the brain. The muscles that are used to blink are facial nerves, which start at the brain stem.

That said, I have a hard time believing that someone can change the iris but cannot move the eyeball. I think those are fed by the same nerve bundle.

I was wondering about this, and if they can move their eyes, with eye-tracking software they can do a hell of a lot better than binary Y/N. That said, I'm very sure the people in charge of this know way better than I do.

That said, I have a hard time believing that someone can change the iris but cannot move the eyeball. I think those are fed by the same nerve bundle.

The circuitry is pretty complicated. As best I can tell from my books, most of the controls for eye movements run through cranial nerve III, but some run through cranial nerves IV, and VI. The axons that control dialation and constriction also run through cranial nerve III. So if III is intact and the other damaged, you could lose at least partial control of eye movement without effect on control of the pupil.

And "upstream" of the nerves, control of the pupil (and focus) is part of the autonomic nervous

That said, I have a hard time believing that someone can change the iris but cannot move the eyeball. I think those are fed by the same nerve bundle.

From what the article is describing, I'd have to say this is not an example where you simply have interruption of outgoing "twitch this muscle fiber" signals along a particular tract. As mentioned before by other posters, the Cranial Nerves emerge from the brain prior to where the spinal cord exits (except for CN 11, which is an oddball), so even a completely cut cord will leave them working.

Rather, the damage has occurred at a higher level such that the message isn't being sent in the first place. Trick

I sincerely hope that by the time I might get to that state that the idiots who oppose euthanasia have been recognised as the nutjobs that they are and that I can be put out of my misery. If you kept a dog in that state (in the UK at least) you would be prosecuted for cruelty.

We let dogs die as quickly and painlessly as possible because they have no soul. A person, especially a good Christian must receive all the medical care possible to maximize your suffering, because it's clearly god's will that you are suffering and just letting you die would be a sin. You do know that if you take your own life you'll burn in hell forever, don't you? Anyway, if god doesn't want you to suffer, he would have seen to it that you don't -- so you must have done something to deserve it if you are

It's an interesting approach but it seems like an EEG, that monitors brainwaves and allows control through that would be better, the article touches on that briefly and rules it out as too expensinve/time intensive to setup. But modern EEG's don't really take that much setup and are cheap (you can buy one from NeuroSky for $79 that has one sensor that goes across your forehead and connects through wireless usb for example) I'd much rather see research going on there than pupil dilation.

I have an Emotive unit, and it's pretty terrible at brainwave detection. What it is slightly better at is detecting the movements of facial muscles. If you use the gyroscope output and then couple that with monitoring something like eyeblinks, you can have a pretty decent hands free headmouse (though it's annoying to have to close your eyes in order to click things). Most of the ~~awesome~~ demos that you see of it on youtube are based on detecting a combination of the gyroscope and facial movements, not a